Category page with gallery for each post

install an image gallery plugin like this one http://wordpress.org/plugins/image-gallery-reloaded/ and have a gallery set in each of your posts, then edit your theme’s category template and have a look at the loop, if it uses the_excerpt() then you have to alter it to the_content().

This way, you will have a gallery list in the category list view. You may want to use another plugin, but keep the same idea.